Fuel pumps, such as those used in high pressure common rail systems, typically use a fluid, such as oil or fuel for lubrication. Many conventional fuel pumps use cam shafts to drive pistons to provide pressure to the fuel system (e.g., high pressure fuel rails).
Many of the conventional fuel pumps have various voids between the cam shaft and the pump housing (e.g., the cam shaft lobes). In many instances, the voids may contain oil used to lubricate the moving parts of the fuel pump and aid in heat dissipation.
Often, the volume of lubricating fluid may cause additional work to be performed because the oil may begin to move due to proximity to the cam shaft, which may be rotating. The rotation or movement of the lubricating fluid, or windage, may increase the amount of work required for the fuel pump and, thus, is a source of parasitic power loss in many conventional fuel systems.
A need therefore exists to address issues of reducing the oil volume and windage in conventional and future fuel systems.